Hibernate 5.1 logs an ugly but benign exception when using an in-memory
HSQL database when it tries to drop a non-existent constraint.

This commit changes the Spring Data REST sample to use H2 rather than
HSQL. This prevents the unwanted exception from occurring as Hibernate's
H2 dialect returns false from dropConstraints.

Instead of using a @Bean, it is better to use an opaque factory
for an internal dependency that users are not going to want in
the context. OAuth2RestTemplate is a common enough bean type that
creating on in autoconfig makes it hard for users to add their own
for business use.

See gh-5967

* pr/5975:
  Remove unchecked casts

Closes gh-5975

Improve the message thrown when a @PropertyMapping is used in
combination with a @Component to include the actual annotations that
are causing the problem.

Fixes gh-5897

Deprecate `PropertiesConfigurationFactory.setProperties()` since it was
only being used in tests.

Fixes gh-5930

Fixes gh-5933

The `if` in registerSpies() is not required as it's covered by the
Assert check.

Closes gh-5889

Closes gh-5883

Closes gh-5934

This commit removes the creation of a `@Primary` `OAuth2RestTemplate`
and updates the documentation accordingly.

Once #5507 is implemented we could revisit this area to provide a way for
users to easily create such a bean.

Closes gh-5202

Closes gh-5965

Closes gh-1440

Closes gh-5964

Closes gh-5963

Closes gh-5962

Closes gh-5961

Closes gh-5960

Closes gh-5959

Closes gh-5958

Closes gh-5957

Closes gh-5955

Closes gh-5953

Closes gh-5952

Closes gh-5951

Closes gh-5950

Closes gh-5940

Closes gh-5949

Closes gh-5947

Closes gh-5946

Closes gh-5945

Previously, arguments passed to the script were handled in one way
if a service was being started using start-stop-daemon and in another
way if start-stop-daemon wasn’t available or the application is being
launched in run mode. This meant that quoted arguments were only 
handled correctly when the application was being started using
start-stop-daemon.

This commit updates the launch script so that argument handling is
the same across all three different way that the application can be
launched.

Closes gh-5942

This commit validates that a `SessionRepository` has been configured if
Spring Boot is meant to auto-configure one.

Closes gh-5943

Commit b7e7bcf7 made `spring.session.store-type` explicit which means that
users of Spring Session in 1.3 have to set that property to restore the
auto-configuration support in 1.4.

This commit implicitly set the store type to redis if redis is present
and log a warning inviting the user to actually specify that in
configuration.

The entry in the auto-configuration report also mentions that such
arrangement is deprecated.

Closes gh-5838